<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <script>
        // 字面量和表达式
        // var str1 = "hello"; //将字面量赋值给变量
        // var str2 = "world";
        // var result = str1 + str2; //将表达式赋值给变量；返回值："helloworld"
        // console.log(result);
        // 算数运输运算符
        // var num = 188
        // console.log(num++ + ++num);
        // 比较运算符，返回值是一个布尔类型:true\false
        // console.log(20 == "20")
        // console.log(1 !== "2") //最佳实践
        // console.log(1 === "2") //最佳实践
        //逻辑运算符
        // var username = "admin";
        // var password = "123456"
        // console.log(username === "aadmin" && password === "123456");
        // var username = "testttt"
        // console.log(username === "admin" || username === "test");
        // console.log(!false)
        // 赋值运算符
        var x = 10;
        var y = 20;
        y += x;
        // y = y + x;
        console.log(y);

    </script>
</body>
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